John 13:5
After that, He poured water into a basin and began to wash the disciples’ feet, and to wipe them with the towel with which He was girded.

Jesus takes on the form of a servant and slave as He washed the feet of the disciples.
They have witnessed Him doing many acts of servitude but nothing like this. Plus, He was performing it on them.
Peter balks at the thought but gives in to letting Jesus wash his feet.
We are not here to lord over others. We are here as servants to others.
Jesus gives us this example to follow.
Matt 23:11 – He who is greatest among you shall be your servant.